package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器,支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
            throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //获取本次请求的URI
        String requestURI = request.getRequestURI(); // /backend/index.html
        log.info("拦截请求:{}", requestURI);

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/favicon.ico",
                "/sendSmsTest/sendMsg",
                "/user/sendMsg",
                "/user/login",
                "/user/sendSmsTest"
        };
        if (request.getSession().getAttribute("user") !=null){
            log.info("用户已登录,用户id为:{}",request.getSession().getAttribute("user"));
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request,response);
            return;
    }

        //判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        //如果不需要处理,则直接放行
        if (check) {
            log.info("本次请求{}不需要处理", requestURI);
            filterChain.doFilter(request, response);
            return;
        }
        //判断登录状态,如果已登录,则直接放行
        if (request.getSession().getAttribute("employee") != null) {
            Long employee = (Long)request.getSession().getAttribute("employee");
            log.info("用户名已登录,用户名id为{}", employee);
            BaseContext.setCurrentId(employee);
            filterChain.doFilter(request, response);
            return;
        }
        log.info("用户未登录");
        //如果未登录则返回登录结果,通过输出流方式向用户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }


    //路径匹配,检查本次请求是否需要放行
    public boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
